Paste-like substances such as toothpaste have historically been dispensed from flexible metal or plastic tubes. When the tube is squeezed, the paste is extruded from a nozzle at an end of the tube. However, collapsible tube-type paste dispensers are rather unsightly. Studies have shown that up to 80% of toothpaste tubes remain on a sink or counter, never being stored in a cabinet or draw. Therefore, a tube of toothpaste, particularly when deformed or rolled up, is considered an eyesore.
Also, a collapsible tube is not a particularly hygienic package for dispensing a substance such as toothpaste which is ingested into the body. Studies have found that such tubes can acquire a host of germs through contact of the tube nozzle with successive toothbrushes. Germs on one brush are transferred to the nozzle of the tube, where build up of toothpaste provides a fertile ground for germs to multiply. Therefore, when another brush contacts the nozzle, those germs are transferred to the second brush. As a practical matter, because of the viscosity of the paste, brushes must often be brought into contact the tube nozzle in order to sever the extruded beads of paste.
In an effort to avoid the above disadvantages of collapsible tubes, various types of paste dispensers have been developed which are designed to be more permanent. These permanent dispensers appeal to consumers because of their durability, styling and convenience. Some of these prior dispensers are designed to accommodate a standard toothpaste tube. Actuation of the dispenser results in the squeezing of the tube and the ejection of the paste from the tube. Examples of such dispensers are disclosed in U.S. Pat. Nos. 3,917,118, 4,418,840 and 4,258,864. However, these permanent dispensers which utilize tube inserts, require significant force to deform the tube and thus dispense the paste. This is inefficient from an energy standpoint. Also, the mechanisms required to effect the tube deformation are usually rather complex, resulting in products which cannot be priced low enough to appeal to a mass market. Also, some of these prior dispensers require an extension nozzle which results in toothpaste remaining in a portion of the dispenser after the empty tube is discarded. Accordingly, when a new tube of paste is mounted in the dispenser, there is carryover of paste from the old tube to the new tube. This is objectionable to many consumers.
As a solution to the problems inherent in toothpaste tubes and dispensers which use replacement tubes, pump dispensers have been developed. These usually consist of a container of paste with a finger-actuated pump at the top of the container. When the pump is actuated, paste is drawn from the container and ejected or extruded from a nozzle in the pump. Although these pump-type dispensers generally contain less paste than a tube, they minimize the amount of paste wasted when the pump is discarded. Also, because a pump-type dispenser does not deform, it is more esthetically pleasing when left exposed on a countertop.
However, conventional pump-type dispensers also have certain disadvantages. Some do not provide closures for the pump nozzles. Therefore, the paste at the nozzle opening in contact with the air tends to harden producing a paste build-up around the nozzle orifice. This exposed paste is not only unsightly, it also promotes the growth of bacteria around the dispensing nozzle. In extreme cases, the hardened paste residue can even occlude the nozzle orifice making it difficult to pump fresh paste from the dispenser.
Some prior reusable dispensers and pump-type dispensers are relatively complex, being composed of many different metal and plastic parts which are difficult to make and to assemble. This complexity results in products that cannot be priced inexpensively enough to capture most of the mass market. Moreover, they are not environmentally friendly because they are difficult to recycle being composed of a mix of metal and plastic parts. In fact, to many consumers, they are considered examples of overpackaging.
Additionally, most conventional pump-type paste dispensers are not ergonomically designed to be actuated in situ. Invariably, the user has to pick up and hold the dispenser in one hand while holding the toothbrush in the other hand. The user must then maneuver the dispenser over the brush while pressing down on the pump trigger or actuator with the thumb to deposit paste onto the brush. Sometimes the pump trigger must be depressed more than once to dispense the desired amount of paste. Finally, a movement to produce a shearing action is required to separate the extruded bead of paste from the dispenser nozzle. This is usually done by wiping the brush against the nozzle. Thus, until now, this type of dispenser has had the same propensity from accumulating and transferring bacteria and germs as the old toothpaste tube discussed above.